1. Field of the Invention
The present invention relates to an authentication apparatus and an image forming apparatus including the authentication apparatus and, more specifically, to a technique for reducing the trouble of re-authentication.
2. Description of the Background Art
As one type of information processing apparatuses, an image forming apparatus (typically a copy machine) has been introduced to many places of business (companies and offices). Image forming apparatuses having a plurality of operational modes including a copy mode, an image communication mode (typically a facsimile mode), a network compatible printer mode and a scanner mode, such as an MFP (MultiFunction Peripheral), are increasing in number.
An image forming apparatus such as an MFP is typically shared by a plurality of users. When one image forming apparatus is shared by a plurality of users, it becomes difficult to grasp usage conditions. Further, such an image forming apparatus may be installed at a location where many people including outsiders come in and go out. In such a situation, it is difficult to maintain security.
In view of the forgoing, recently, it becomes more common to allow use of an apparatus after a log-in process (user authentication), in order to improve security level and to mange use conditions user by user. Log-in process allows use of the image forming apparatus by only the logged-in user and, therefore, the security level can be improved. Further, log-in process allows inspection of individual use history of the image forming apparatus and, hence, management of use condition user by user becomes easier.
On the other hand, if a logged-in user moves away from the image forming apparatus without a log-out operation, the logged-in state is maintained and, therefore, a different user can use the image forming apparatus utilizing the log-in state of the previous user (user name).
If the logged-in user always logs out when he/she moves away from the image forming apparatus, such a problem can be avoided. Users, however, often forget to log-out. Thus, a technique of automatically performing the log-out process (cancelling authentication) when the apparatus is not operated for a given time period in the logged-in state has been known.
Further, in connection with such a problem, Japanese Patent Laying-Open No. 2006-302199 (hereinafter referred to as '199 Reference) discloses a technique of monitoring a user who logged-in to an information processing apparatus through biometric authentication and locking the information processing apparatus when the user is detected to have moved away from the apparatus.
When the conventional art described above is used, once the log-out process takes place and the same user is to use the image forming apparatus, user authentication is required anew. Re-authentication is troublesome for the user. Particularly if the same user is to use the image forming apparatus soon and re-authentication of the user is required, it would be burdensome for the user. Such a problem cannot be solved by the technique disclosed in '199 Reference.